1 This International Standard applies to cold-reduced carbon steel strip with a carbon content over 0,25 % (mlm) made from steels specified in Table 1. It is commonly produced in thicknesses of 6 mm and under, and in widths up to 600 mm exclusive, in coils and cut lengths. The strip is ordered in the as-delivered condition, as specified in 1.4 or clause 5, and is predominantly used for springs, but also for other highly stressed parts of many different types. Steel designations CS 55 to CS 95 may be supplied in the quenched and tempered condition.
2 This International Standard does not apply to alloy steels or stainless steels.
3 Cold-reduced carbon steel strip is furnished in the following types:
— full hard, where a very stiff, springy product is produced to obtain full hardness after the final rolling (it is intended for flat work not requiring the ability to withstand cold forming);
— annealed, which is intended for applications requiring moderate cold forming;
— quenched and tempered, which is intended generally for the production of steel springs where the appropriate combination of strength, hardness, toughness and ductility can be achieved;
— intermediate hardness, which is intended for applications where cold-forming is slight or where a moderately stiff, springy product is needed.
The cold-reduced carbon steel strip qualities appropriate to the particular grade shall be:
a) full hard quality: material rolled to the final thickness with a minimum hardness as shown in Table 2;
b) annealed quality: annealed to the hardness or tensile strength shown in Table 3;
c) quenched and tempered quality: quenched and tempered steel strip for steel designations of CS 55 and over, tempered to the properties shown in Table 4 or Table 5;
d) intermediate quality: temper rolled to the hardness range shown in Table 6 by a controlled amount of cold rolling after annealing.
4 The material shall be ordered to either hardness or tensile strength requirements, but not to both (see Tables 2, 3, 4, 5, and 6).
5 Cold-reduced carbon steel strip is characterized by close dimensional tolerances and good surface finish and, in the cold-rolled and quenched and tempered condition, it is possible to attain high values for hardness and tensile strength.
ISO 4960:1999 history
2019ISO 4960:2019 Steel strip, cold-reduced with a mass fraction of carbon over 0,25 %
2007ISO 4960:2007 Cold-reduced carbon steel strip with a mass fraction of carbon over 0,25 %
1999ISO 4960:1999 Cold-reduced carbon steel strip with a carbon content over 0,25 %
1986ISO 4960:1986 Cold-reduced carbon steel strip with a carbon content over 0,25 %